1. Field of Invention
The present invention relates to a flush system, and more particularly to a method and arrangement for controlling flush water volume during a flushing operation.
2. Description of Related Arts
Urinal and toilet flush systems have been well-known as one of the most significant inventions in the last century. A conventional toilet or urinal flush system comprises a valve body having a water inlet and a water outlet, a diaphragm having a water channel communicating between the water inlet and the water outlet, a relief valve disposed at the diaphragm for blocking the water flowing from the water inlet to the water outlet through the water channel, and a flush actuator arranged to move the relief valve at a position where the water is allowed flow to the water outlet for completing the flushing operation.
Conventionally, the relief valve has a pivotal pin member longitudinally and downwardly extended therefrom in the water channel, whereas the flush actuator comprises an elongated actuating member transversely and pivotally extended from the valve body, and a pusher pin transversely and movably extended in the valve body to align with the pivotal pin, in such a manner that when the elongated actuating member is pivotally moved in a predetermined direction (such as a downward direction with respect to the valve body), the pusher pin is transversely pushed to drive the pivotal pin to pivotally move within the valve body so as to open the relief valve for allowing water flowing through water channel. As a result, a user is able to flush the toilet by actuating the flush actuator.
A major drawback for this conventional toilet flush system is that the user is unable to control the volume of water flow so that unnecessary waste of water is prevalent. In other words, the conventional flush system will allow a standard time and volume of flushing regardless of purpose thereof. For example, when the user wishes to flush away a certain piece of toilet paper in the toilet bowl, he or she is unable to adjust the volume of flushing water so that the flushing cycle in this particular instance is exactly the same as any usual flushing cycle for this particular flush system. This is obviously undesirable from environmental as well as economical point of view.
There exist several types of flush systems which include certain types of water adjustment mechanisms which are claimed to be capable of controlling the volume of water during a typical flush cycle. However, the major problem for these kinds of water adjustment mechanisms is that their efficacy of effectively controlling the volume of flushing water among a plurality of operation modes is in doubt. For example, a conventional flush system equipped with a conventional water adjustment mechanism may have two modes of operations, namely a regular flush cycle and a water-saving flush cycle, in which the latter is supposed to require less water than the former. However, the reality is that very often, there is no noticeable or significant difference in water consumption between these two modes of operations so that there is no practical distinction between these two modes of operations. From engineering point of view, when the water adjustment mechanism produces no significant difference in water consumption, there is actually no reason or incentive to produce a flush system having such a water adjustment mechanism because it will certainly increase the manufacturing cost of that flush system.
It is submitted that the main reason for this ineffectiveness in controlling the volume of flush water is that one is hard to accurately control the period for which the relief valve is opened by one single actuating member. Thus, it is possible that the time of opening the relief valve in the two modes of operations is very much the same so that there is no noticeable difference in water volume between these two modes of operation.